Fish transporting apparatuses of this kind, also known as oscillating or vibrating conveyors, are used in the fish processing industry to transport fish in a desired direction, for example towards a fish processing machine. Owing to their structure and surface properties, fish have a preferred transport movement which depends on different factors and/or parameters. In the fish, the scale structure, the presence of fins (tail, ventral, dorsal and pectoral fins), the gill covers and/or other properties such as e.g. the weight and geometric properties are such factors or parameters. These factors or parameters are used to transport the fish in a desired direction, by e.g. using the force of gravity or the rough scale structure of the fish as a drive (impulse). By the example of the scale structure, transport is effected by the scales so to speak “catching” on a rough surface of the transport device. Due to the oscillating or vibrating movement of the transport device, the fish with their scale structure are repelled on the rough surface, which leads to the headfirst transport movement. The preferred transport movement of the fish is therefore not only in relation to the scale structure headfirst.
Corresponding devices for aligning the fish in a head/tail orientation have a fish transport device of this kind. The fish, which are already aligned with the fish processing machine headfirst in the preferred transport movement (direction of transport), are transported headfirst by the oscillation/vibration in the direction of the fish processing machine which is provided there. The fish with a tail-first orientation in the direction of the fish processing machine are transported by oscillation/vibration in the opposite direction away from the fish processing machine in the direction of a turning device, turned through 180° in the turning device in such a way that, after turning, the fish lie on the fish transporting apparatus with their heads in the direction of the fish processing machine, and then delivered to the fish processing machine.
From DE 195 11 489 A1 is known a fish transporting device for automatically feeding fish to a fish processing machine according to the preamble of claim 1.
It is also known from practical experience that ordinary oscillating or vibrating conveyors or the like can be provided with a surface structure which assists transport of the fish in the preferred direction. In this case the closed surface of the bottom element can be provided e.g. with grooves, furrows or the like cut transversely to the direction of transport, which assist transport of the fish. In further fish transporting devices used in practice, e.g. conventional sandpaper is applied to the surface of the bottom element, in order to assist the possibility of the fish “catching” on the bottom element. But transport of the fish is made difficult by the fact that the fish are usually wet and have a slimy layer or coating on the outside. As a result, rubbing and/or “catching” of the fish on the surface structure of the bottom element is made difficult. This concerns in particular fish of the trout species, but also salmon and other species. The known fish transporting apparatuses, however, have several drawbacks. Firstly, the speed of transport is limited on account of the fish properties on the one hand and the surface structure of the bottom element on the other hand. Furthermore, the surface structure of the bottom element is only suitable for transporting fish of a smaller size. Secondly, such fish transporting apparatuses can be cleaned only with difficulty. To put it another way, the known fish transporting apparatuses do not meet the hygiene requirements required in the food industry, because the water and/or slime stays on the bottom element and can be removed only by additional flushing. Moreover, so-called “dirt traps” in which remains of the fish lodge are formed by the grooves, furrows or the sandpaper, which can lead to contamination of subsequent fish.